Downhole temperature, pressure and fluid flow sensors are important tools used by the energy industry in measuring and evaluating hydrocarbon production from wellbores in earth formations. Such sensors are utilized to monitor downhole conditions so that production decisions can be made without direct wellbore intervention. Production monitoring systems using play important roles as numerous operators rely on it for performing their daily well management functions. In addition, models of formation and production systems are utilized in conjunction with such monitoring systems to assist in predicting and forecasting production performance, which is important for effective reservoir management and control.